Alert archive / Massachusetts / Tornado Warnings in 2023

Tornado Warning 1, NWS Boston/Norton, MA

July 16, 2023Essex County, Middlesex County, Massachusetts

NWS Boston/Norton, MA issued this tornado warning at Jul 16, 2023, 8:17 AM EDT for Essex County, Middlesex County, Massachusetts. It was in force for 28 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 16, 2023, 8:17 AM EDT (12:17 UTC)
Expired: Jul 16, 2023, 8:45 AM EDT
In force: 28 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

Counties Essex County, MA, Middlesex County, MA

The radar

The Boston radar (KBOX), 67 km from the middle of the area, began a volume at 12:21 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Jul 16, 8:35 AM EDT	TSTM WND DMG	Chelmsford, MA	tree down on Old Stage Rd - relayed by amateur radio.
Jul 16, 8:35 AM EDT	TSTM WND DMG	Chelmsford, MA	tree down on Old Stage Rd - relayed by amateur radio.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Gray, ME (KGYX), launched 12:00Z, 0.3 hours before the alert went out and 178 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 399 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 454 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 146 m²/s²
0-3 km storm-relative helicity: 128 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.8

Open this sounding in Storm Lab

The text

As transmitted.

682 
WFUS51 KBOX 161217
TORBOX
MAC009-017-161245-
/O.NEW.KBOX.TO.W.0001.230716T1217Z-230716T1245Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Boston/Norton MA
817 AM EDT Sun Jul 16 2023

The National Weather Service in Boston/Norton has issued a

* Tornado Warning for...
  West central Essex County in northeastern Massachusetts...
  Northeastern Middlesex County in northeastern Massachusetts...

* Until 845 AM EDT.
    
* At 817 AM EDT, a severe thunderstorm capable of producing a tornado
  was located over Maynard, or 9 miles northeast of Marlborough,
  moving northeast at 30 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Lowell, Billerica, Chelmsford, Westford, Acton, Concord, Bedford, 
  Groton, Littleton and Carlisle around 825 AM EDT.
  Tyngsborough around 830 AM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4240 7142 4244 7154 4269 7150 4268 7114
TIME...MOT...LOC 1217Z 213DEG 27KT 4245 7144 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

KC

1 follow-up statement

969 
WWUS51 KBOX 161232
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
832 AM EDT Sun Jul 16 2023

MAC009-017-161245-
/O.CON.KBOX.TO.W.0001.000000T0000Z-230716T1245Z/
Essex MA-Middlesex MA-
832 AM EDT Sun Jul 16 2023

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 845 AM EDT FOR WEST
CENTRAL ESSEX AND NORTHEASTERN MIDDLESEX COUNTIES...
    
At 832 AM EDT, a severe thunderstorm capable of producing a tornado
was located over Carlisle, or near Chelmsford, moving northeast at 30
mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Lowell, Methuen, Billerica, Chelmsford, Andover, Dracut, 
  Tewksbury, Westford, Tyngsborough and Carlisle around 835 AM EDT.
  Lawrence around 840 AM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4248 7137 4251 7147 4269 7150 4268 7114
TIME...MOT...LOC 1232Z 213DEG 27KT 4254 7136 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

KC

The office that day

Everything else NWS Boston/Norton, MA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 16, 8:15 AM EDT	Severe Thunderstorm Warning	BOX	Essex, Middlesex, Worcester	45 min
Jul 16, 8:43 AM EDT	Tornado Warning	BOX	Middlesex	22 min
Jul 16, 9:02 AM EDT	Special Weather Statement	BOX	Worcester	43 min
Jul 16, 9:23 AM EDT	Flash Flood Warning	BOX	Hampden, Hampshire	3 hr
Jul 16, 9:30 AM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Worcester	45 min
Jul 16, 10:10 AM EDT	Tornado Warning	BOX	Middlesex, Worcester	20 min
Jul 16, 10:16 AM EDT	Severe Thunderstorm Warning	BOX	Hampden, Hampshire, Worcester	44 min
Jul 16, 10:49 AM EDT	Flash Flood Warning	BOX	Hampden, Worcester	3 hr
Jul 16, 10:53 AM EDT	Flash Flood Warning	BOX	Middlesex, Worcester	3 hr
Jul 16, 11:50 AM EDT	River Flood Warning	BOX	Worcester	6 hr
Jul 16, 11:53 AM EDT	Special Weather Statement	BOX	Essex	52 min
Jul 16, 12:24 PM EDT	Areal Flood Warning	BOX	Essex, Middlesex, Norfolk, Suffolk	3 hr
Jul 16, 12:48 PM EDT	Special Marine Warning	BOX		27 min
Jul 16, 1:36 PM EDT	Flash Flood Warning	BOX	Bristol	6 hr
Jul 16, 1:55 PM EDT	Areal Flood Warning	BOX	Hampshire	88 min
Jul 16, 2:06 PM EDT	Special Weather Statement	BOX	Essex	54 min
Jul 16, 2:19 PM EDT	Flash Flood Warning	BOX	Bristol, Essex, Middlesex, Norfolk, Plymouth, Suffolk and 1 more	5 hr
Jul 16, 5:29 PM EDT	Flash Flood Warning	BOX	Bristol, Plymouth	4 hr
Jul 16, 7:51 PM EDT	River Flood Warning	BOX	Hampden	36 hr

Nearby

Tornado Warnings in Massachusetts, 2023 Every tornado warning in 2023 Tornadoes in 2023

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.